.subject {
	font-size: 30px;
	color: red;
	text-align: center;
}

.bt {
	font-size: 20px;
	color: green;
	text-align: center;
}

.zw {
	font-size: 15px;
	color: black;
}

.key {
	text-decoration: bold;
	color: red;
}

body {
	line-height: 30px;
}